To efficiently use heating energy of a heating element by designing a storage bag in such a manner that a storage bag made of an air impermeable material is provided with an opening, which blocks air circulation when closed, and a heating element, which generates heat when in contact with oxygen, is put into an air permeable bag.

A storage bag 2 for a heating element 1 is a transparent bag made of an air impermeable material (synthetic resin), which is provided with an opening 3, and when the opening 3 is closed, air circulation between the inside and outside is blocked. The heating element 1 is made in such a manner that a heating composition, which generates heat when in contact with oxygen, is put into an air permeable bag, that is, a disposal pocket body warmer. When in outdoor place, a user can use the disposal pocket body warmer, and when in indoor place, he/she puts the disposal pocket body warmer in the storage bag 2 to stop oxidation, and if he/she wants to use the disposal pocket body warmer, he/she can take out it of the storage bag 2 anytime.